The present invention relates to satellite communications systems. In particular the present invention relates to downlink beam power gating techniques particularly adapted to beam hopped multiple payload frame structures.
Satellites have long been used to provide communications capabilities on a global scale. Since the inception of the modern communications satellite, however, one factor has remained constant: the limited availability of power on board the satellite. The limited availability of power persists today even in the face of tremendous advances in satellite technology.
Major drains on satellite power include the communications reception equipment used to receive the uplink and the transmission equipment used to generate the downlink. The transmission equipment in particular often requires 50% or more of the total power generated by a satellite. Furthermore, downlink power amplifiers are far from 100% efficient and therefore waste power whenever they are active.
Any undue drain on satellite power is undesirable. Thus, for instance, limitations on satellite power may prevent a satellite from encoding and decoding heavier and more error protective coding techniques. As another example, limited satellite power may reduce the number and type of observational or sensing functions which a satellite may perform.
In addition, as satellite technology has progressed, it has become more common for satellites to process their uplinks. In other words, the satellite may decode, process, route, queue, and otherwise manipulate data before recoding and packaging the data into downlink frames. Thus, the utilization of the downlink depends on the amount of data ready and waiting to be transmitted. Transmitting partially empty frames can be a waste of power, and can have detrimental impacts on the satellite performance through unnecessary servicing of queues, for example.
A need has long existed in the industry for a gated power time division downlink that addresses the problems noted above and others previously experienced.